What are you making it out of? I would suggest metal duct tape, not
the grey plastic kind, on the outside joints.You could probably use
foam weatherstripping or just make a friction fit for you cover or
door. A small glass container to hold the acetone at the bottom with
a platform placed in it with legs or over it. Have you thought of
using one of those rubber reptile heating pads for your heat source.
They should get warm enough to evaporate acetone without risking
exposure to a spark. You could place it under the glass dish.
I have never made one of these, but just throwing out some
brainstorming ideas.
I saw some guys on Kickstarter invented a device that spins the part
in a bath of acetone for a timed amount of time. It has a hinge that
turns the holder/spinner over the solution and then turns it for an
amount of time and then appears to retract it.